Expanding rivets are known to be used for the creation of permanent joints between two components, with the transmission force primarily generated by a form fit. They can replace joints made from screws, discs and nuts where the joint does not need to be released again or where release is even undesirable.
Conventional expanding rivets are made from a bolt with a rivet head and an expanding rivet body. For riveting, the expanding rivet body is pushed through the rivet holes previously punched or drilled into the components to be joined, e.g. the mounting panel. The expanding rivet is held at the already existing rivet head with a tool as a brace, and the free end of the expanding rivet body is deformed by pressure or impact onto the closing head. This method of riveting can only be used for riveting connections which are accessible from both sides.
For installation at locations which are only accessible from one side, so-called blind rivets are often deployed. These consist of a hollow rivet with a mandrel passing through its middle from the rivet head, which presses against the expanding rivet body of the hollow rivet, and a drawing section protruding beyond the rivet head, which is connected to the mandrel via a predetermined breaking point. For riveting, the blind rivet is inserted into the rivet hole with the rivet head on the outside, until the rivet head makes contact to the component surface. Afterwards, the rivet mandrel is pulled into the rivet by applying a strong force to the drawing mandrel. This expands and deforms the rivet body. The drawing mandrel breaks at the predetermined breaking point. The required tensile force can only be applied by means of force-enhancing tools.
Expanding rivets, which can be mounted from a single side, are not consistently free of play within the range of supported forces. This means that if a force below that of the maximum rated value is applied, shifting of the joined components is possible.
Furthermore, expanding rivets currently have to be mounted from both sides in order to obtain a connection which is play-free. This is inconvenient or impractical, especially in radio frequency (RF) applications, e.g. for larger assemblies such as antennas. Such a connection has been disclosed, for instance, in German Patent DE 19840014 C1.
For this reason, one object of this invention is to provide an expanding rivet connection which can be installed from a single side and which supports the joined components up to the rated load and creates a play-free connection between them. This purpose is achieved by the features described in claims 1 and 14 of the invention. Advantageous embodiments are the subjects of the dependent claims.